Clinton cleaned up in Mississippi, winning 83 percent of the vote, according to The Associated Press. Sanders, on the other hand, finished with just 16 percent, 1 point above the threshold to win delegates. That gave Clinton an estimated 28 delegates, compared to just one for Sanders by the AP’s count, with seven more unaccounted for at midnight.

The tight margin in Michigan will likely prevent Sanders from narrowing the delegate gap, despite his win there. The AP projected Sanders the winner with 50 percent of the vote to Clinton’s 48 percent. That will give him at least 63 pledged delegates to Clinton’s 52, the AP reports, with another 15 left outstanding. As long as those delegates are bound around the state’s margin, Clinton win the Tuesday night delegate haul.

The problem for Bernie Sanders is that small wins aren’t good enough. Sanders is behind, so he needs to roughly 70% of awarded delegates to cut into Hillary Clinton’s lead. The margin of defeat for Bernie Sanders in the South is what is hurting his campaign in the race for the nomination. Sanders has been completely blown out in numerous Southern states with larger delegate counts. In contrast, the states that Sen. Sanders has won big in are smaller states who award fewer delegates.

The Clinton campaign has been through the primary process before, and their experience shows in the way that they have put an emphasis on large margins of victory in the states where she is leading. The win in Michigan was great for Sen. Sanders regarding momentum and fundraising, but it did nothing for him in terms of getting closer to winning the Democratic nomination.

Former Sec. Clinton currently leads Sen. Sanders 1,221-571 in delegates. If Hillary Clinton wins half or less of the remaining 2,973 delegates, she will win the Democratic nomination. The Democrats proportional delegate rules mean that the only way Bernie Sanders can catch up to Hillary Clinton is to win by large margins in the remaining states. Winning narrowly is not going to get the job done for Bernie Sanders.

The margin of victory matters in the Democratic primary process, so Bernie Sanders needs to win the remaining big delegate states by a large margin in order to have a shot at becoming the nominee.

If Hillary Clinton keeps doing exactly what she is currently doing, she will be the Democratic nominee.